Milk and food

So my son has been on breast milk without any supplements. (He was born January 5th) i have had thrush 3 times and mastitis 3 Times the last time resulting in 20 days of antibiotics. Bc of all this I had stopped pumping and now he has eaten through all my stash. He breast feeds morning and night and I still seem to have a decent amount. He has 20 days left of breast milk stored so I called his doctor and he said instead of putting him through a month and a half of formula just to start whole milk early and he would prescribe a vitamin since I was really worried about him getting all his nutrients. Has anyone else done cow milk yet? Also I’m really terrified of him choking so I have not given much finger foods can you all post pics of some of the finger foods you give?